What best describes details about an individual's private life that are not public?

Personal information is the most appropriate term to describe details about an individual's private life that are not public. This encompasses various types of data that relate to an individual's identity, characteristics, and personal circumstances, which are not meant to be disclosed. Personal information can include items such as social security numbers, medical history, financial details, and private communications.

While confidential information also pertains to matters that should remain private, it often implies a legal or formal obligation to keep those details hidden, which may not cover the broader scope of personal matters. Sensitive data generally refers to information that, if disclosed, could cause harm or distress to an individual, but it is a more specific subset of personal information. Public records, on the other hand, are documents and information that are officially published and accessible to the public, which inherently does not classify as private. Hence, personal information best captures the concept of individual details that should be kept private and are not meant for public consumption.